UMD Theses and Dissertationshttp://hdl.handle.net/1903/3
Fri, 16 Mar 2018 05:16:23 GMT2018-03-16T05:16:23ZImpact of Isotopic Heterogeneity in Shallow Systems on Modeling of Stormflow Generationhttp://hdl.handle.net/1903/20540
Impact of Isotopic Heterogeneity in Shallow Systems on Modeling of Stormflow Generation
Kendall, Carol
A major uncertainty in hydrologic and geochemical modeling of stormflow generation in watersheds has been quantification of the contributions of water and solutes from different sources and hydrologic pathways to streamwater. Isotopic techniques have recently gained widespread acceptance as useful tools in the investigation of sources of stream flow, but considerable debate still surrounds the question of whether the spatial and temporal variations in the isotopic and chemical compositions of water components are negligible. At Panola Mountain, Georgia, a 2-year study of temporal and spatial variability in rain and throughfall has determined that average throughfall is enriched by 0.5% in 0^18O and 3.0% in 0D relative to rain; site-specific differences in canopy cause up to 1.2 % variation in 0^18O among collectors for the same storm; and throughfall ^18O enrichment takes place throughout the storm, not just at the beginning. Evaporative losses are greater and throughfall is generally slightly enriched in ^18O in conifer forests relative to deciduous forests. However, throughfall shows little evidence of evaporative fractionation; instead, the high deuterium-excess values suggest considerable exchange with re-evaporated waters. A 490-m^2 artificial catchment in China was used to investigate the effects of temporal variations in rain composition, and temporal and spatial variations in dominant water flowpath, on the development of isotopic and chemical heterogeneity in soil waters and groundwater. In response to changes in storm intensity, variability in the amounts of water transported via piston versus macropore flow caused a 4% range in 0^18O of groundwaters. Selective storage of early rain in shallow soils makes characterization of the isotopic composition of infiltrating rain water problematic. Seasonal and hydrologic differences in the sources of alkalinity were investigated at four watersheds at Catoctin Mountain, Maryland, by analyzing the dissolved inorganic carbon in streamwater for 0^13C. Because of short residence times, the isotopic signatures of the two primary carbon sources, calcite and soil-derived carbonic acid, do not appear to be appreciably overprinted by exchange reactions, biological recycling, or degassing; hence, 0^13C seems to be a useful semi-conservative tracer of water flowpaths and carbon sources.
Fri, 01 Jan 1993 00:00:00 GMThttp://hdl.handle.net/1903/205401993-01-01T00:00:00ZThe Relationships Between Racial Discrimination, Gender Discrimination, Childhood Socialization Messages, and the Self-Esteems of Professional Black Womenhttp://hdl.handle.net/1903/20539
The Relationships Between Racial Discrimination, Gender Discrimination, Childhood Socialization Messages, and the Self-Esteems of Professional Black Women
Brown, Jacqueline Finney
This study investigated the relationships between perceived racial discrimination, perceived gender discrimination, childhood socialization messages and the global and situational self-esteems of Professional Black women. The sample population was 119 Professional Black women. The Tennessee Self-Concept Scale Form C was used to measure global self-esteem. The Survey of Black Women's Perceptions was used to measure degree of self-esteem enhancement of childhood socialization messages, levels of success related to the Life Tasks of Work, Love, Friendship, and Relationship to God, and perceived frequency of experiences of racial and gender discrimination. The hypotheses were that the global self-esteems and the situational self - esteems of Professional Black women would be affected by perceived racial discrimination, perceived gender discrimination, and childhood socialization messages, and that the global self-esteems of Professional Black women would be affected by the Life Tasks of Work, Love, Friendship, and Relationship to God. Pearson product moment correlation and multiple regression analyses were used to test the hypotheses. Although some of the findings were tentative and suggestive, the findings regarding global self-esteem, and the Life Tasks of Love and Friendship were highly significant. Global self-esteem was positively affected by all of the Life Tasks in general, by the Life Tasks of Love and Relationship to God in particular, and by gender discrimination from white men on the job. Global self-esteem was negatively affected by gender discrimination from white males outside of work. Global self-esteem was inversely correlated with racial discrimination from other Blacks outside of work and with gender discrimination from white males outside of work. Global self-esteem was positively correlated with all of the Life Tasks. The Life Task of Love was negatively affected by childhood socialization messages from women outside the family concerning what it meant to be female. The Life Task of Friendship was affected overall by the interaction of racial discrimination, gender discrimination, and childhood socialization messages, and in particular by childhood socialization messages from women outside the family concerning what it meant to be Black. Hypotheses concerning situational self-esteems related to the Life Tasks of Work and Relationship to God were not supported.
Tue, 01 Jan 1991 00:00:00 GMThttp://hdl.handle.net/1903/205391991-01-01T00:00:00ZMary Shelley and Utopian Domesticityhttp://hdl.handle.net/1903/20538
Mary Shelley and Utopian Domesticity
Sites, Melissa Jo
In her seven novels and other writings, Mary Shelley critiques traditional restrictive domestic ideology while developing a feminist utopian vision of domesticity. She begins with Wollstonecraft's prescription for women's education and adds Godwin's ideas of simplicity, frankness, and forgiveness. Domesticity fosters these very conditions. Ernst Bloch's theory of the utopian function within ideology shows how the false consciousness of domestic and Romantic ideology can bear a utopian impulse. To provide a historical context of domesticity in feminist and reform thought, I discuss the emphasis on education, the importance of community, and the life of the mind in companionate marriage in Mary Astell, Sarah Scott and Margaret Cavendish; I then show how Adeline Mowbray by Amelia Opie and The Empire of the Nairs by James Lawrence illustrate the effects of putting Godwin's and Wollstonecraft's theories into practice. I look at Shelley's exploration of Romantic ideology in Frankenstein while countering prevalent critical misreadings of its nascent ideal of utopian domesticity. I then explore how Mathilda, Midas, Proserpine, and Maurice, or the Fisher's Cot develop contrasting ideas of utopia and dystopia around isolation and community. In her political novels, Valperga, The Last Man, and Perkin Warbeck Shelley developed Wollstonecraft's feminist theories and focused on women's relation to political power. Valperga's Euthanasia exemplifies the powerful Wollstonecraftian citoyenne and Shelleyan Romantic hero. The Last Man illustrates the priority of personal over public concerns, while Perkin Warbeck questions the legitimacy of political ambition. In her domestic novels, Lodore and Falkner, Shelley creates utopian domesticity by modifying Godwin's political system and by revising the Byronic Romantic hero; in Falkner, she rewrites Godwin's Caleb Williams according to a feminist idea of social justice. I conclude by looking at Persuasion by Jane Austen, Records of Woman by Felicia Hemans, and Helen by Maria Edgeworth, which demonstrate awareness of the potential benefits and drawbacks of domesticity, but were less concerned than Shelley with feminist critique.
Tue, 01 Jan 2002 00:00:00 GMThttp://hdl.handle.net/1903/205382002-01-01T00:00:00ZThe Influence of Student and Teacher Field Independence/Dependence Cognitive Style on Student Achievement in High School Chemistryhttp://hdl.handle.net/1903/20537
The Influence of Student and Teacher Field Independence/Dependence Cognitive Style on Student Achievement in High School Chemistry
Custer, Thomas Alan
The study examined the relationship between field dependence/independence of students and teachers on student achievement in high school chemistry as measured by the American Chemical Society's Test. The hypothesis was that differences in field dependent/field independent cognitive styles of students and teachers should not affect achievement in high school chemistry. Field independent learners are task oriented, set self-regulated goals, seek less guidance in problem solving and prefer to work individually. Field dependent learners are attuned to social interaction, favor structure, teacher direction and feedback and benefit from instruction in problem solving. Participants in the study were high school chemistry teachers and their 10th, 11th, and 12th grade general chemistry students enrolled in four public comprehensive high schools. The measures used to collect the data were the Embedded FiguresTest (EFT) (Karp and Konstadt, 1971) and the American Chemical Society's High School Chemistry Test (ACS) (1991). The selected teachers represented extremes in field dependence/independence. Students of the selected teachers comprised the student group and totaled 272. Students were administered the EFT and ACS tests the first week of the second semester and teachers followed their typical instructional program. The ACS post test was administered to students during the last week of the semester. The basic design was two by two, field dependence/independence of students matched to field dependence/independence of teachers. Data analysis was conducted using the SPSS-X statistical package and included analysis of covariance. The covariant was the pretest results of the ACS test since the students were not randomly assigned. The analysis of covariance indicated student scores on the ACS test were not significant when compared to field dependent/independent teachers and the null hypothesis was not rejected. The findings showed clearly that students with strong independent learning styles showed significantly higher chemistry achievement and greater achievement gains. Further research needs to be conducted with a culturally diverse randomized student and teacher population, several reliable measures of chemistry achievement and data collection over a longer period of time.
Sat, 01 Jan 1994 00:00:00 GMThttp://hdl.handle.net/1903/205371994-01-01T00:00:00Z